Description  House finches are sparrow-sized birds. Males are reddish with heavy, brown streaks. Females are brown birds with heavy brown streaks on white under parts. House finches differ from purple finches by the male purple finch's purple side streaks (unlike the brown streaks in a house finch) and by the female's conspicuous eye stripe (female house finches lack this feature.) In the Black Hills, house finches could be confused with Cassin's finches, but the house finch has much heavier ventral streaking and lacks the Cassin's finch's back streaking. Female house finches are harder to distinguish, but are generally less boldly patterned.

House finches owe their red color to carotenoid pigments in their food; occasionally you may see yellow or orange individuals, if their diet lacks these pigments. Female house finches, however, prefer to mate with the reddest males they can find.

The song of the house finch is described by Peterson as "bright, loose, and disjointed" like a house sparrow, but more musical.
 
 

Distribution The spread of the house finch across eastern North America has been a startling ornithological event. This bird is native to the western United States, including the Black Hills, but its spread to eastern South Dakota has come from the east. In 1940, house finches were introduced to Long Island, New York and they have spread back westward ever since. The species was first observed in Aberdeen in 1985. Sightings of the species in eastern South Dakota were frequent by the early 1990's, as can be seen by the Aberdeen banding data in Table 1. The species is now abundant across the state.

 

Natural History

House finches almost always are found in settled areas with houses, lawns, and small conifers. They are generally absent away from human habitation. House finch diets include mostly vegetable matter. They are abundant at bird feeders, where they prefer sunflower seeds.

House finches are early nesters, beginning in March in most of the country. Most females nest more than once a year, some re-nest even before the first broods are fledged. The species uses a wide variety of nesting sites, but prefers coniferous trees. Nests have also been found in vents, ledges, ivy on buildings, hanging planters, and even abandoned nests of other birds. Females do most of the nest building and all of the incubating, although the male does bring her food. If he does not bring enough food, the female may abandon the nest. She lays between 3 and 6 speckled, blue-white eggs. Eggs can be briefly exposed to subfreezing temperatures without apparent harm. After hatching, females take egg shells away from the nest. Both sexes carry fecal material from the nest. The young develop rapidly and leave the nest after about two weeks. In late summer, young birds form large flocks (sometimes in the hundreds), especially near food sources.

Since their introduction, house finches have become migratory. In South Dakota, we do not have yet enough data to describe
migration patterns. However, it is likely that many of our wintering birds are not the same as summer populations.

Eastern populations of house finches have been vulnerable to a virus that results in horribly crusty eyes, killing or blinding most of the affected birds. The Cornell Laboratory of Ornithology has a citizen monitoring program that follows the spread of this conjunctivitis, first seen in Massachusetts and Maryland in 1994. The disease was first reported in South Dakota in 1996. Cornell also has other bird monitoring projects in which classrooms could participate. To participate in the Cornell programs, contact them at 159 Sapsucker Woods Road, Ithaca NY 14850 or at their WEB site:

http://www.birds.cornell.edu/netcommunity/Page.aspx?pid=1478

Conservation Measures

Across their range, house finches flock to areas of human development. Near people, the finches find food, cover, and fewer wild predators. House finches are not reported to be agricultural pests in South Dakota, despite their love for sunflower seeds at feeders.
House finches, unlike house sparrows that were introduced to the United States from Europe, are native to North America.
Therefore, the species is protected by federal law as are all native songbirds. It is illegal to harm the birds or disturb their nests.

Glossary

Carotenoid - red and yellow pigments related to the compound carotene found in some plants.
Coniferous - trees that reproduce from cones. Most coniferous trees retain their leaves throughout the year.
Conjunctivitis - inflammation of the conjunctiva, the transparent covering of the eye.
Fecal - referring to excrement; body waste.
Fledged - having feathers and the ability to fly and leave the nest.
Ventral - the underside or belly of an animal.

Hill, Geoffery E. 1993. House Finch (Carpodacus mexicanus). In The Birds of North America, No. 46 (A. Poole and F. Gill, Eds.)
Philadelphia: The Academy of Natural Sciences; Washington D. C.: The American Ornithologists' Union.
Peterson, R.T., 1980. A Field Guide to the Birds, 4th edition, Houghton Mifflin, Boston.
South Dakota Ornithologists' Union, 1991, The Birds of South Dakota, NSU Press: Aberdeen, SD.
Terres, John K., 1980, The Audubon Society Encyclopedia of North American Birds, Alfred A. Knopf: New York.

Written by:
Dr. Dan Tallman, Northern State University, Aberdeen, SD 57401. 1997.

Reviewed by:
Dr. David Swanson, Biology Department, University of South Dakota, Vermillion, SD.

Publication of the House Finch fact sheet was funded by the South Dakota Department of Game, Fish and Parks, Division of
Wildlife, Pierre, SD.